JAPS1ME/README.md

JAPS1ME

JAPS1ME - Just A PS1 Memory Card Editor is a command-line tool for managing PlayStation 1 memory-card saves for RetroArch-style emulators. It converts DexDrive (.gme) card images to RetroArch (.srm) format, lists the saves on .gme and raw (.srm/.mcr) card images, and imports, deletes, and installs saves and cards.

Made for	Developed on

Features

• Convert DexDrive .gme files (including headerless/zeroed-header variants) to RetroArch .srm with validated stripping.
• Import a named save from a .gme file (or a raw card misnamed .gme) into a RetroArch .srm card, with duplicate and free-space checks.
• Delete saves from a .srm card by slot number or save name.
• Copy an emulator .srm out of the RetroArch saves directory into this workspace for JAPS1ME work (bare file name or prefix; asks before overwriting).
• Install a .srm card into your RetroArch saves directory (remembers the directory, backs up the replaced card).
• Browse saves with slot numbers, save names, Shift-JIS game titles, regions, block counts, payload sizes, and free slots.
• Read-only list; convert validates before writing and never overwrites an existing output file.

Build

You need a Rust toolchain with Cargo installed.

cargo build --release

The executable is created at target/release/japs1me.

Usage

Command	Purpose
japs1me --version	Print the version (-V is also supported).
japs1me list <CARD.gme|CARD.srm>	List saves and free slots.
japs1me convert <INPUT.gme> <OUTPUT.srm>	Convert a DexDrive .gme file to RetroArch .srm.
japs1me import <CARD.srm> <SOURCE.gme> <SAVE-NAME>	Import a save from a .gme (or raw misnamed .gme) file into a .srm card.
japs1me delete <CARD.srm> <SLOT-OR-SAVE>	Delete a save from a .srm card by 1-based slot number or save name.
japs1me copy <SOURCE.srm> <DEST.srm>	Copy an emulator .srm into the workspace for JAPS1ME editing; bare source names resolve in the saves directory.
japs1me install <SOURCE.srm>	Install a .srm card into the configured RetroArch saves directory.

Examples:

target/release/japs1me list save-games/pro-evolution-soccer-2.22507.gme
target/release/japs1me convert save-games/pro-evolution-soccer-2.22507.gme pes2.srm
target/release/japs1me import mysaves.srm save-games/pro-evolution-soccer-2.22507.gme BESLES-03946PES-OPT
target/release/japs1me delete mysaves.srm BESLES-03946PES-OPT
target/release/japs1me copy "ISS Pro Evolution (USA).srm" /tmp/work.srm
target/release/japs1me install mysaves.srm

list

• Accepts .gme files and raw images (.srm, .mcr, …) detected by size and MC signature.
• Shows each save's 1-based slot, save name, game title (Shift-JIS decoded, falling back to the save name), region, block count, payload size, and active/deleted status.
• The footer reports free slots out of 15. Directory checksum mismatches and orphaned links are reported as warnings on stderr.

convert

• Accepts DexDrive .gme input only (134976 bytes with an MC signature at offset 3904). Files with a missing/zeroed header are accepted with a warning.
• A raw 131072-byte input is rejected with an “already a raw .srm image” error; copy or rename it instead of converting.
• Writes the raw 131072-byte payload verbatim via a temporary file; existing output files are not overwritten.

import

• Copies one save (matched by exact save name, e.g. BESLES-03946PES-OPT) from a .gme source into a raw .srm card, using the first free slots in slot order. A raw 131072-byte source starting with MC is also accepted (with a warning) for .gme files that are actually misnamed raw images.
• If the save already exists on the target, asks Save <name> already exists on <card>, overwrite it with the one from <source>? (y/n) on interactive terminals. Only y/yes proceeds; anything else cancels and leaves the card unchanged. The old save is freed first, so replacements with a different block count work.
• When stdin is not a terminal, an existing save is a hard error instead of a prompt.
• Link bytes are relinked to the new slots, the size field is recomputed, and touched directory checksums are regenerated. Identity bytes (region, product code, identifier, title, save data) are preserved verbatim; saves imported from a deleted source slot are normalized to active.
• The target is staged in a temporary file, re-validated, and only then replaced.

delete

• Deletes one save selected by 1-based slot number (the save's initial slot, as shown in list) or exact save name. All-digit selections are slot numbers.
• The save's slots are reset to formatted with fresh checksums and zeroed data, freeing them for future imports.
• .srm targets only; the updated card is staged, re-validated, and only then replaced.

copy

• Pull an emulator save out of the RetroArch saves directory into this workspace copy, so list/import/delete work happens here and the emulator original is never modified (raw .srm, 131072 bytes starting with MC).
• A bare source file name (no /) that does not exist as given resolves inside the configured RetroArch saves directory (./.japs1mesavedir wins over the global config when both exist); paths with a separator or that exist literally are used as-is. An exact file-name match wins; otherwise a prefix match applies: no match errors out, one match is used, and several show a numbered picker.
• An existing destination asks Overwrite <dest> with <source>? (y/n) on interactive terminals; only y/yes proceeds. Piped stdin fails instead of overwriting. Copying a file onto itself is refused.
• The destination is staged in a temporary file and re-validated before it becomes visible.

install

• On first use (no saved directory configured), asks for your RetroArch PS1 core's saves directory and saves it as a single line ($XDG_CONFIG_HOME is honored when set; falls back to ./.japs1mesavedir when no user config directory resolves, e.g. on Windows). A ./.japs1mesavedir file in the invocation directory overrides the global config when both exist, so a workspace can point elsewhere.
• When the source file name exactly matches a .srm in the saves directory, that card is inferred and the numbered picker is skipped. Otherwise scans the directory for .srm files and asks which one to overwrite (numbered, single attempt). A second strict y/yes confirmation follows; anything else cancels.
• Backs up the existing card to <name>.srm.japs1me-bak first (refuses to proceed if that backup already exists), then replaces the target's contents in place so the filename still matches the game's .cue basename.
• Prompts require an interactive terminal; piped stdin fails with an error instead.

Safety

• Back up saves before converting.
• convert refuses to overwrite; delete or rename a previous .srm first if you intend to replace it.
• import and delete replace the target .srm after staging and validation; back it up first and keep RetroArch closed while modifying it.
• install backs up the overwritten card automatically, but keep an independent backup of anything irreplaceable.
• Avoid testing against your only copy of a save; the fixture in save-games/ is read-only test input.

Design compared with JAPS2ME

JAPS1ME's CLI mirrors JAPS2ME, but the workflow differs because the emulators manage cards differently:

• PCSX2 and its derivatives share one memory card across many games, so JAPS2ME trades in single-save containers (.cbs/.max) imported into a shared card.
• RetroArch and PS1 emulators like PCSXR instead use one memory card per game, with the .srm basename matching the disc image. Whole-card convert and install are therefore the primary workflow here.
• Importing individual saves out of a shared card image only makes sense from .gme DexDrive archives (raw images misnamed .gme are also accepted as sources), so import is limited to .gme/raw sources; there is no single-save (.mcs/.psx) support.

Scope compared with MemcardRex

JAPS1ME focuses on .gme → .srm conversion, save listing, and save importing rather than general memory-card editing:

• list covers saves and free slots; there is no per-frame browser.
• convert handles DexDrive .gme only; there is no VGS/VMP/MCX support and no reverse conversion.
• import copies whole saves from .gme (or misnamed raw) into .srm; there is no single-save (.mcs/.psx) support and no import into .gme.
• There is no GUI, card formatting, comment editing, or hardware (DexDrive/serial) support. JAPS1ME validates directory checksums read-only and never recalculates them, except when relinking frames during imports and resetting them during deletions.

For details about the card formats, see the technical format guide. The save-games collection lists the saves shared in this repository.

Tests

Run formatting, tests, lint checks, and a release build from the repository root:

cargo fmt --check
cargo test
cargo clippy --all-targets -- -D warnings
cargo build --release

License

Copyright (C) 2026 Mark Robillard Jr (MARKMENTAL).

JAPS1ME is licensed under the GNU General Public License, version 3 or (at your option) any later version (SPDX: GPL-3.0-or-later). See LICENSE for the full text. This project license does not automatically apply to the individual save files in save-games/; see that directory's README for contribution and attribution guidance.

Acknowledgements

Thanks to ShendoXT and the MemcardRex project, an advanced PlayStation 1 memory-card editor. Its implementation provided a valuable technical reference for understanding the PS1 memory-card and DexDrive formats.